1 CupertinoNavigationBar
iOS风格的导航栏. 通常和CupertinoPageScaffold一起使用
2 构造函数
CupertinoNavigationBar({ Key key, this.leading, this.automaticallyImplyLeading = true, this.automaticallyImplyMiddle = true, this.previousPageTitle, this.middle, this.trailing, this.border = _kDefaultNavBarBorder, this.backgroundColor, this.brightness, this.padding, this.actionsForegroundColor, this.transitionBetweenRoutes = true, this.heroTag = _defaultHeroTag, })
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3 常用属性
3.1 leading：导航栏左侧组件,leading优先级高于previousPageTitle
leading: Icon(Icons.arrow_back),
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3.2 automaticallyImplyLeading：是否显示左边组件
automaticallyImplyLeading : true,
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3.3 automaticallyImplyMiddle：是否显示中间组件
automaticallyImplyMiddle : true,
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3.4 previousPageTitle：导航栏左侧组件的右边的文本
previousPageTitle : "返回",
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3.5 middle：导航栏中间组件
middle: Text("标题"),
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3.6 trailing：导航栏右侧组件
trailing: Image.asset( "lib/assets/sample/image.jpg", width: 25.0, height: 25.0 ),
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3.7 backgroundColor：背景色
backgroundColor: Color(0xfff1f1f1),
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3.8 padding：内边距
padding: EdgeInsets.symmetric(vertical: 20.0,horizontal: 10.0),
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3.9 actionsForegroundColor：左侧默认组件和左侧组件右边文本的颜色
actionsForegroundColor: Colors.red,
